Add a line after 1 line after match in Ex mode

Question

I need to search for a string in a file, then I need to some text after one line following the first match. I need to perform this for a number of files in a script.

I am trying to use vim ex mode for this. I know :/search_string can perform a search but I am not able to figure out how to move the cursor down and insert the line. Will sed or awk be more suitable for this?

I need to do this in a script.

Answer 1

Load your files into vim:

vim files

Then, we will use a command on each of them via :argdo. The command searches (:/pattern/+1) and opens a new line:

:/pattern/+1 normal! oYour new text here

Another option is to put from the expression register

:/pattern/+1 put ='Your text here'

Altogether:

argdo /pattern/+1 put ='text'

This may struggle if any of the files don’t contain pattern.

From my answer on scripting ex:

ex file <<EOF
/pattern/+1 put ='text'
wq
EOF

Answer 2

I know this is late & maybe I am misunderstanding the requirements, but you can do this in POSIX ex, without vim extensions.

Simply (a)ppend any text following a match, optionally with a number of additional lines. The . is not a typo, you need that to exit the append.

For this overly complex example, ^H is CTL+v,CTL+h (i.e. col -b)

LANG=C ex -s <<'EOF'
r!man true
g/.^H/ s///g
"%!sed "s/.`printf '\b'`//g"
/Exit/+1a
****
ALL MY STUFF
****
.
%p
wq! true.txt
EOF

The extras are just to give you some other ideas. /pattern/+1i would do the same thing, but (i)nsert before, etc.